Removable shear knife assemblies



S. F. JUDD May 26, 1964 REMOVABLE SHEAR KNIFE ASSEMBLIES Filed March 6, 1961 I 2 Sheets-Sheet 1 INVENTOR. SEBASTIA N F. J UDD ATTORNEYS y 26, 1964 s. F. JUDD 3,134,286

REMOVABLE SHEAR KNIFE ASSEMBLIES Filed March 6, 1961 2 Sheets-Sheet 2 INVENTOR. SEBASTIAN F. JUDD United States Patent F 3,134,286 REMQVABLE SHEAR KNIFE ASSEMBLIES Sebastian F. Judd, 2437 N. 91st St, Milwaukee, Wis. Filed Mar. 6, 1961, Ser. No. 93,565 6 Claims. (Cl. 83700) This invention relates to improvements in removable shear knife assemblies.

In the use of baling presses, scrap shears, and similar devices, it is common practice to have a shear knife on the ram head which coacts with a shear knife on the bed so as to cut off material, which is part way in the machine cavity, as the ram is moving to shearing position. The shear knife elements proper are usually rectangular in cross section and are usually removably mounted in a rabbet groove in the ram head or bed. It is common practice in this type of construction, after wear occurs on the active leading corner which forms the cutting edge of the knife, to remove the knife elements and replace them in an interchanged position so as to make a different corner the active shearing edge. Inasmuch as there are four corners to a knife element of rectangular cross section, the original knife elements may be used in four different positions before sharpening is required. After all four of these corner edges have been worn, the knife elements must be removed from the machine for grinding. When replaced in the ram head or bed after grinding, it is necessary to utilize shims to take up the space previously occupied by the ground-off material. In conventional construction, it takes a mechanic a long period of time to get just the right amount of shirnming in order to have the outer surfaces of the knife elements of the bed in perfect alinement with the corresponding surfaces of the knife in the ram head. Inasmuch as there are usually several knife elements, the tedious shimming work must be carried out with each element.

It is a general object of the present invention to provide an improved shear knife assembly which greatly facilitates the replacement of the knife elements after grinding.

A further object of the invention is to provide an improved shear knife assembly wherein a plurality of knife elements are removably mounted in a novel manner in a knife holder whereby the knife elements may be perfectly installed in the holder while the latter is removed from the baling press or the like, with the tedious shimming performed off of the ram head or bed. With this arrangement, the knife elements, properly assembled in the holder, may ultimately be quickly replaced in the ram head, bed, or other device without requiring the latter to be out of operation for any substantial length of time for such installation.

A further object of the present invention is to provide an improved shear knife assembly wherein there is a novel sliding nut arrangement with the nuts carried in slots on the knife holder and head, and wherein there are cap screws which connect the knife elements to the holder and head and engage said sliding nuts, this arrangement providing for compensation due to dimensional changes caused by grinding of the knife elements.

Other objects of the invention are to provide a shear 3,134,286 -Patented May 26, 1964 of a machine showing the removable knife elements and holder;

FIG. 2 is a fragmentary sectional View taken on the line 22 of FIG. 1;

FIG. 3 is a fragmentary sectional view taken on the line 33 of FIG. 1; 5

FIG. 4 is a fragmentary sectional view taken on the line 4-4 of FIG. 1; and

FIGS. 5, 6, and 7 are views corresponding to FIGS. 2, 3, and 4, respectively, showing the knife elements reinserted in the holders and machine after grinding, and showing shims in position.

Referring more particularly to the drawings, the novel knife assembly may be employed either for horizontal or vertical movement and on various machines employing removable knife elements. In FIG. 1 the numeral 10 designates, by way of example, the forward portion of the ram head of a baling press. The same knife holding arrangement, however, may also be employed on the bed knife of a baling press. In FIG. 1 the top surface of the ram head is designated by the numeral 11 and the front side of the ram head constituting a surface at right angles thereto and which shows in FIGS. 2, 3 and 4, is designated by the numeral 12, this being the side which leads when the ram is being moved forwardly toward a cooperatingshearing knife on the bed. At the leading upper corner of the ram head is a rabbet groove 13 which extends the full width of the ram. In a conventional construction such groove is of less size in cross section than that shown and directly receives the knife elements.

In the present invention the rabbet groove 13 is of larger knife assembly which is relatively simple in construction, i

cross sectional size to removably receive a knife holder 14 which is L-shaped in cross section so that it also has a rabbet groove. The. shorter or inner wall of the knife holder has a plurality of vertical bores 15 through the width of said wall for receiving cap screws 16 which have threaded lower ends 16. threadedly engaging tapped holes 17 in the ram head as shown more particularly in FIG. 2. The heads 18 of the cap screws are accommodated in enlarged counterbores 19.

The bottom or longer wall 26 of the knife holder is provided with spaced slots 21 which are parallel to one an other and each of which is adapted to receive a nut 22. The slots 21 extend into the bottom of the bottom wall 20 through part of the thickness of said wall only as shown in FIG. 2. In the remaining thickness portion is a plurality of shorter slots 23 which are in communication with the slots 21. I

The knife elements, which are formed of a suitable tool steel are indicated by the numeral 24. They may beof any selected length. In FIG. 1 there are three of such knife elements which fill up the width of the rabbet groove 13. These knife elements fit into the rabbet groove 25 of the knife holder and each of the knife elements is provided with a first series of bores 26 for cap screws 27, as shown in FIG. 2, and with a second series of bores 28 for receiving relatively long cap screws 29, as shown in FIG. 3. Each cap screw 27 has a threaded inner end which is threaded into one of the nuts 22. The head of each cap screw 27 is received in a counterbore 30 and ingly positioned counterbore 34' to receive the same head when the knife'elements are reversed in position.

ans-ease In addition to the removable holding means heretofore described, the knife elements are removably held in position in the holders by a third set of cap screws 35', as shown in FIG. 4, which pass through slots 37 and have threaded inner ends threaded into tapped openings of nuts 35, the latter being accommodated in slots 37 on the inner face of the inner wall of the knife holder. The heads of the cap screws 35 are accommodated in counterbores 38, and each knife element has oppositely disposed counterbores 33 for accommodating the heads of the cap screws 35 when the knife elements are reversed from the position of FIG. 4.

It is desirable to have the faces of the rabbet groove 25 about If off of square with respect to face (It) so that the edge (a) of a knife element is offset outwardly from face (h) about 1 while the corner of the knife element at (d) is flush with ('h). This reduces wear along surfaces (g),

-(h) and it The knife holder is additionally removably held in position by a second set of cap screws39 which have threaded inner ends tapped into threaded openings as in the ram head as shown in PEG. 4, the outer ends of said cap screws having heads which are accommodated in counterbores 21.

In the use of the improved shear knife assembly, when the knife elements are new they are as shown in FIGS. 2, 3 and 4 with the outer forward corner (a) (FIG. 3) serving-as the shearing edge. When the edge (a) becomes Worn the cap screws 27, 2% and 35 may be removed and the knife elements reversed in the holder to bring the corners (Z2) into the position formerly occupied by the corners (a). After such reversal, the cap screw head counterbores 34), 3d and 38' accommodate the heads of their respective cap screws. After the corners (b) become worn, re-arrangement of the knife elements in the knife holder recess 25 will bring into active position the corners (c) andultimately the corners (d). All of this is conventional practice, and may be done without shimrning until all four corners have been worn. Thereafter, any additional wear requires a regrinding of the knife elements, and the insertion of shims to take up the space formerly occupied by the ground-off material. Heretofore such shimming has been done directly on the machine while installing the reground knife elements. This was a tedious operation and the mechanic would spend a large amount of time trying to get just the right amount of shimming to bring the forward faces of the knife elements into exact alinement with the respective faces on the machine, such as the sides 12 of the ram head, and to bring the other exposed faces of the knife elements into proper alinement with the faces of the machine in which installed, such as the top face 11 of the ram head. During such work the machine was out of use.

With the present invention, when regrinding of the knife elements is necessary, the entire knife assembly including the novel holder 1 is removed by removing the cap screws 16, 29 and 39. This is a simple operation. With the present invention it is possible to stock spare holders so that another holder with resharpened knife elements may be immediately inserted in the machine to permit continued use of the machine. In the meantime, the removed holder with its knife elements can be taken to a bench, the knife elements removed and sent out for regrinding. Thereafter, they may be assembled in the holder while it is oh of the machine, a suitable number of shims as required being inserted on the bench and before the reground knife elements in the holder are reinstalled in the machine. Referring to FIG. 5, shims are usually necessary as at 45 between the inner vertical walls of the knife elements and the corresponding Wall of the L -shaped holder 14. When reassembled, the nuts 22 will slide enough in the slots 21 to compensate for the shimming at 45 and the shank of the cap screws 27 will correspondingly move relative to the slots 23. If the only shimming which is required is in the location 45, then the knife elements are reinstalled in the machine, the nuts 31 of FIG. 6 sliding in the slots of the machine head to compensate for the shimming at 45, and the shanks of the cap screws 29 moving relative to the slots id and 33 as shown in FIG. 6. Thus, on the bench the leading faces (2) (FIG. 5) of the knife elements may be lined up with the face (f) of the holder while on the bench so that when the holder is installed on the machine the latter operation may be quickly accomplished, the movement of the nuts 31 in the slots 32 compensating for the changes in the position of the cap screws 29.

If there is wear in a plane at right angles to the knife faces (e) so that a face such as the face (g) must be ground, then shimming mayalso be required at 47, usually a much lesser amount than at 45'. This shimming may also be accomplished on the bench while the holder and knife elements are removed from the machine, the nuts 35 in the holders moving sufhciently in the slots 37 as shown in FIG. 7 to compensate for the amotmt of shimming at '17. In certain types of machines such as a shear shimming at 4-5 is not necessary, as it is not necessary in shears to have face (e) in line with face (f). t

The insertion of the shims 47 is performed accurately on the bench to bring the faces (g) (FIG. 5) of the knife elements into alinement with the faces (h) on the holder while on the bench, then when the holder with the installed and regr-ound knife elements is reinstalled in the machine, there is bound to be proper alinement with the top surface 11 of the ram'head.

From the above it is apparent that the present invention makes it possible to reinstall reground knife elements in a novel holder on the bench, and to perform all of the tedious shimming operations Without tying up the machine which vis involved. After the knife elements have been properly installed in the holder, then the holder may be quickly installed in a machine for use in the shimmed condition as is clear from FIGS. 5, 6, and 7.

It is to be understood that the present invention is not to be limited to the exact details of construction shown and described, for obvious modifications will occur to persons skilled in the art.

What I claim is:

1. A shear knife assembly for use in a machine having an elongated corner groove comprising a readily rcmovable elongated knife holder having a groove, at least one knife element positioned in said groove and having at least one face alined with a corresponding face of said holder, adjustable means securing said knife element to said holder only, which means is adjustable relative to said holder to compensate for shimming after grinding of said alined face whereby the knife face may be aligned with said holder face while the holder and knife are removed from the machine, means carried by said holder for removab-ly securing said holder in the groove of said machine part, and adjustable means extending through said knife element and holder for additionally securing said holder in the groove of said machine par-t, said last mentioned means being adjustable relative to said machine part and relative to said holder to compensate for a change in position after said shimming whereby the holder with the knife may be installed on the machine without disturbing the alignment between the knife face and holder which has been previously made while the parts were removed from the machine.

2. In a machine part having an elongated corner groove with a wall and having a slot adjacent said wall, a nut slidable in said slot, \a readily removable elongated knife holder having a groove, at least one knife element positioned in said groove and having at least one face alined with a corresponding face of said holder, said face of the holder also being alined with a corresponding face aligned with said holder face while the holder and knife are removed from the machine, and .a cap screw extending through said knife element and holder and threaded into said nut in the machine pant slot for securing said holder in the groove of the machine part, said holder having a slot through which said cap screw passes, which latter slot is so disposed as to provide for a change of position of said cap screw relative to said holder to compensate for said shimming, and said nut being adapted to move in the machine part slot in a direction to also compensate [for said shimming whereby the holder with the knife may be installed on the machine without disturbing the alignment between the knife face and holder which has been previously made while the parts were removed from the machine.

3. In a machine part having an elongated corner groove with a wall and having a slot adjacent said wall, a nut slidable in said slot, a readily removable elongated knife holder having a groove, at least one knife element positioned in said groove and having at least one face alined with a corresponding face of said holder, said face of the holder also being alined with a corresponding face of said machine part, adjustable means securing said knife to said holder only, which means is adjustable to compensate for shimming after grinding of said alined face of the knife element whereby the knife face may be aligned with said holder face while the holder and knife are removed from the machine, means carried by said holder independently of said knife element removably securing said knife holder in the groove of said machine part, and a cap screw extending through said knife element and holder and threaded into said nut in the machine part slot for additionally securing said holder in the groove of the machine part, said holder having a slot through which said cap screw passes, which latter slot is so disposed as to provide for a change of position of said cap screw relative to said holder to compensate for said shimming, and said not being adapted to move in the machine part slot to also compensate for said shimming whereby the holder with the knife may be installed on the machine without disturbing the alignment between the knife face and holder which has been previously made while the parts were removed from the machine.

4. A shear knife assembly for use in a machine part having a rabbet groove comprising a readily removable elongated knife holder adapted to fit said rabbet groove of the machine part and itself having a rabbet groove, at least one knife element which is rectangular in cross section positioned in the said groove of the knife holder and having a first exposed face which is aligned with a corresponding face of said holder and having a second exposed face at right angles to said first face which is aligned with a corresponding face of said holder, adjustable means securing said knife element to said holder only, which means is adjustable to compensate for shimming after grinding of one of said exposed faces of the knife element, adjustable means securing said knife element to said holder which is adjustable to compensate for shimming after grinding of said second exposed face of said knife element whereby the knife faces may be aligned with said holder faces while the holder and knife are removed from the machine, and adjustable means extending through said knife element and holder adapted to secure said holder in the groove of said machine part, said last mentioned means being adjustable relative to said machine part and holder to compensate for shimming after grinding of one of said exposed faces of the 6 knife element while the parts were removed from the machine.

5. A shear knife assembly for use in a machine part having a rabbet groove comprising a readily removable elongated knife holder adapted to fit said rabbet groove of the machine part and itself having a rabbet groove, at least one knife element which is rectangular in cross section positioned in the said groove of the knife holder and having a first exposed face which is alined with corresponding face of said holder and having a second exposed face at right angles to'said first face which is alined with a corresponding face of said holder, adjustable means securing said knife element to said holder only, which means is adjustable to compensate for shimming after grinding of one of said exposed faces of the knife element, adjustable means securing said knife element to said holder only, which means is adjustable to compensate for shimming after grinding of said second exposed face of said knife element whereby the knife faces may be aligned with said holder faces while the holder and knife are removed from the machine, means carried by said holder independently of said knife element for removably securing said holder in the groove of said machine part, and adjustable means extending through said knife element and holder adapted to additionally secure said holder in the groove of said machine part, said last mentioned means being adjustable relative to said machine part and holder to compensate for shimming after grinding of one of said exposed faces of the knife element while the parts were removed from the machine.

6. A shear knife assembly for use in a machine part having an elongated rabbet groove comprising an elon gated knife holder of a shape to fit said groove and itself having a rabbet groove and having walls at right angles to one another, at least one knife element positioned in said rabbet groove of the knife holder and having a face which is alined with a corresponding face of said holder and having a second face at right angles which is alined with a second face of said holder, one of the walls of said holder having a slot extending transversely of the width of said wall, a nut in said slot, a cap screw removably connecting said knife element in the holder and having its inner end threaded into said nut, the adjacent wall of the holder having a slot through which the cap screw extends to permit shim compensating movement, the second wall of said holder having a slot, a nut slidable in said slot of the second wall, a cap screw extending at right angles to said first-mentioned cap screw and threaded into said second-mentioned nut to additionally detachably connect said knife element to said holder, there being provision for shim compensating movement of said second cap screw relative to the holder, and means providing for shim compensating relative movement between it and said machine part and between it and the holder and extending through both said knife element and holder for detachably connecting said holder in the rabbet groove of said machine part.

References Cited in the file of this patent UNITED STATES PATENTS 596,530 McCoy Jan. 4, 1898 2,387,767 Nordquist Oct. 30, 1945 2,539,602 Wehr Jan. 30, 1951 2,593,144 Hercik Apr. 15, 1952 2,814,345 Ripper Nov. 29, 1957 3,046,825 Thompson July 31, 1962 

1. A SHEAR KNIFE ASSEMBLY FOR USE IN A MACHINE HAVING AN ELONGATED CORNER GROOVE COMPRISING A READILY REMOVABLE ELONGATED KNIFE HOLDER HAVING A GROOVE, AT LEAST ONE KNIFE ELEMENT POSITIONED IN SAID GROOVE AND HAVING AT LEAST ONE FACE ALINED WITH A CORRESPONDING FACE OF SAID HOLDER, ADJUSTABLE MEANS SECURING SAID KNIFE ELEMENT TO SAID HOLDER ONLY, WHICH MEANS IS ADJUSTABLE RELATIVE TO SAID HOLDER TO COMPENSATE FOR SHIMMING AFTER GRINDING OF SAID ALINED FACE WHEREBY THE KNIFE FACE MAY BE ALINED WITH SAID HOLDER FACE WHILE THE HOLDER AND KNIFE ARE REMOVED FROM THE MACHINE, MEANS CARRIED BY SAID HOLDER FOR REMOVABLY SECURING SAID HOLDER IN THE GROOVE OF SAID MACHINE PART, AND ADJUSTABLE MEANS EXTENDING THROUGH SAID KNIFE ELEMENT AND HOLDER FOR ADDITIONALLY SECURING SAID HOLDER IN THE GROOVE OF SAID MACHINE PART, SAID LAST MENTIONED MEANS BEING ADJUSTABLE RELATIVE TO SAID MACHINE PART AND RELATIVE TO SAID HOLDER TO COMPENSATE FOR A CHANGE IN POSITION AFTER SAID SHIMMING WHEREBY THE HOLDER WITH THE KNIFE MAY BE INSTALLED ON THE MACHINE WITHOUT DISTURBING THE ALIGNMENT BETWEEN THE KNIFE FACE AND HOLDER WHICH HAS BEEN PREVIOUSLY MADE WHILE THE PARTS WERE REMOVED FROM THE MACHINE. 